Summary translation

As a permanent crop, hop is infested by a lot of pests and diseases, which need regular control even in organic farms, because those breweries that use organic hops in principle make the same demands on hop cones as the purchasers of conventionally produced hops. Available hop cultivars possess distinct differences in their susceptibility to diseases. In principle, an organic hop grower will choose resistant or tolerant cultivars. But it is also possible that a brewer for his type of beer needs a specific cultivar that is susceptible to diseases. Downy mildew and powdery mildew, the most important diseases, are controlled in organic farms by products containing copper and sulphur, in combination with stone meal and EMOs (effective micro-organisms). In order to test alternatives to sulphur and copper compounds, the German Federal Agency for Agriculture and Food has funded according researches. Pure biological compounds and products with a reduced copper content were tested. After three years of testing it has to be realized that the pure biological compounds are no alternative to the copper compounds that currently are in practical use, not even under production conditions of an organic farm. An important annual pest is the damson-hop aphid. The pure herbal products Spruzit Neu, NeemAzal and Quassia were tested regarding their aphid control abilities in experimental plots. The compounds were not only sprayed, but alternatively also coated on the vines as an environmentally sound way of application. It was proved for the first time that the active agent of Quassia is transported vertically upwards in the vascular bundles of the plants and that this method is suitable for aphid control in hop.